Gaseous electric discharge device



March 13, 1934. J w MULDER 1,951,163

GASEOUS ELECTRIC DISCHARGE DEVICE Filed Nov. 9. 1932 1 I BY ATTORNEYPatented garter wares GASIEGIUS ELECTRIC EMSCHARGE DEVECIE JohannesGiisbertus Wilhelm Mulder, Eindhoven, I

Netherlands, assignor to General Electric (Company, a corporation of'NewYork Application November in the Netherlands 2 Claims.

The present invention relates to gaseous electric discharge devicesticularly the invention which the electric column type.

generally. and more parrelates to such devices in discharge is of thepositive Such devices have a negative characteristic,

that is, they require an increase of voltage asthe current value isdecreased and for this reason a series connected resistance or otherballasting device is provided to regulate the electric discharge device.used by the device i sistance.

The object of the A considerable part of the total energy I s consumedin this series represent invention is to provide a method and a meansfor operating gaseous velectric discharge devices whereby the ballastingdevice now used in the art is eliminated. A further object-of theinvention is to provide a regulatory means for gaseous vices which ismore known in the art.

vantages attaching to the tion will be apparent to from the followingcomprises a circuit to a gaseous electric electric discharge deefficientthan those now Still further objects and ad-' those skilled in the artparticular description and objects the invention the current supplieddischarge lamp device perithese odically falls to zero and anothergaseous electric discharge regulatory device provided with 'a grid isconnected in series with said lamp device.

I have discovered that regulation of the lamp device is effected .wherethe grid of said regulatory tion to the potential supplied the lampdevice that negative when said the potential supplied to device is insuch relato the electrodes of said grid potential is always electrodepotential becomes positive and does not become positive" until some timethereafter.

Take, for exampl device connected to a ,an electric discharge lampdirect current source and a circuit for said lamp device whereby thecurrent on, the electrodes of said lamp device is periodically reducedto zero by a circuit interrupter. If,

at the instant that zero,'a negativepotential is of the regulatorydevice conn said lamp device, the current flow said electrode current isat impressed on the grid electrodes will not take place even when'theelectrode circuit is again made. tween theelectrodes when thegridpotential The duration of current flow between positive.

Current flow bewill again take place only reaches zero or becomes theelectrodes of the lamp device and therewith the, mean current valuethereof is controlled by device and to its operacted in series withbetween said November 12,1931

increasing, or decreasing the interval between the instant that theelectrode current is atzero and the instant that the grid potentialreaches zero or becomes positive. The discharge current of said lampdeviceis appreciable loss of energy.

When the electric discharge lamp device is operating on direct current,as above, only a v negative potential is applied to the grid of the thusregulated with no go regulatory device, where desired, and a switch Q5is provided in the grid circuit to control the grid potential in suchmanner that the negative potential is applied to said grid only when thecurrent on the electrodes is at zero and is disconnected from said gridat a' predetermined interval after 10 current is again applied to theelectrodes to accomplish the desired result set forth above.

In the preferred the gaseous electric discharge lamp device isconembodiment of my invention nected to a source of alternating currentand an alternating current is applied to the grid of the regulatorydevice, the phase of the grid potential of the regulatory device laggingbehind that of the potential applied to the electrodes of the lampdevice. This phase ple, adjustable means by which the magnitude ofcurrent flow through the lamp device is regulated and the phase lag ischanged, when desired, by a small rotating condenser or a small variableresistance. grid potential the magnitude of current flow through thelamp device is changed and thus the intensity of the light emitted bysaid lamp device is controlled in a simple manner. I

: -Where'the lamp device is connected to an alternating current-sourceit is advantageous that said device have two anodes and to connect aregulatory device having a thermionic cathode,

a grid, and an anode inthe leads of each of said anodes. H Current thenflows through the lamp'device during each half-cycleof the alternatingcurrent. i

lag is accomplished by simso By changing the phase lag of the g In thedrawing accompanying and forming part ice Fig. 3 is a schematic view ofanother embodi V ment of my invention, and v Fig. 4 is a schematic viewof another embodiment of my invention.

' umn type.

Like numbers denote like parts in allthe figures.

Referring to Fig. 1 of the drawing the gaseous electric discharge lampdevice comprises an elongated container 1 having electrodes 2 and 3sealed therein. Said electrodes are cold sheetmetal electrodes and aremade of iron, for example. Said container 1 is filled with a gaseousatmosphere, such as neon, at a few millimeters pressure. Said lampdevice has a negative voltampere characteristic and is of the positivecol- A regulatory gaseous electric discharge device comprising acontainer 4 filled with a gas, such as argon, at a few millimeterspressure and having a thermionic cathode 5, an anode 6 and a grid 7 isconnected in series with said lamp device.

The cathode of the regulatory device and the electrode 3 of the lampdevice are connected to the secondary 12 of. a transformer 11 and theprimary 10 of said transformer 11 is connected and disconnected from theterminals 8 of an alternating current source by switch 9. The cathode 5and the grid 7 of the regulatory device are connected to the secondary18 of the transformer 17, resistance 19 being connected into the currentlead connecting grid 7 with secondary 18. The primary 16 of'saidtransformer 17 is connected into a circuit including an inductance .anda variable resistance 14, said inductance 15 and said resistance 14being connected in parallel and the circuit being connected to theterminals 8. The above described apparatus is started into operation byconnecting the cathode 5 to a suitable source of currentwhich heats saidcathode 5 to its operating temperature. After said cathode has attainedits operating temperature switch 9 is closed and the regulatory deviceand the lamp device are started into operation. Said inductance 15 andsaid resistance 14 are in such relation' to each other that thepotential phase of the secondary 18 lags with respect to the potentialphase of secondary 12 during the operation of the device.

The relation between the two potential phases is indicated in the graphshown in Fig. 2 wherein curve 20 represents the rise and fall of thepotential of secondary 12 and curve 21 represents the rise and fall ofpotential of secondary 18, that is, the potential phase changes of grid7 with respect to said cathode 5. At the instant that the potentialrepresented by curve 20 is at zero there is, of course, no current flowthrough the series connected discharge devices. Even though thispotential becomes positive and increases to the point that the flow ofcurrent would normally occur through said device no current flow takesplace if the potential represented by curve 21 is negative and thiscontinues until this potential becomes zero or positive. As soon as thepotential represented by curve 21 becomes zero, or positive, the currentstarts to flow in said series con-,

nected discharge devices and continues until the potential representedby curve 20 again becomes zero. Current flow through saidseriesconnected discharge devices is represented by curve 22. The meanvalue of the currentrepresented by line 22 is determined by thepotential phase difference between the potential represented by curve 20and that represented by curve 21 and this phase diflerence and therewiththe mean value of the current is increased, or decreased, as'desired byadjusting variable resistance 14.

From the foregoing it will be understood, of

course, that current flows through said series conof the secondariesemmas nected discharge device only during the positive phase of thealternatin cycle and only during part of that phase, which gives anintermittent effect to the light emitted by the lamp device. If this isnot desired the frequency of the current source may he stepped up to thepoint that, due to the persistence of vision, the .lamp appears to becontinually luminous.

In the embodiment of my invention illustrated in Fig. 3 the gaseous vicehas two anodes and 25 and a thermionic cathode 24 sealed therein. Eachof said anodes 25 is connected in series with the thermionic cathode 5of a regulatory discharge device which is similar in all respects tothat shown in Fig. 1. The anodes 6 of said regulatory devices areconnected to the terminals of the secondary 26 of the transformer 27.The primary 28 of said transformer 27 is connected to the terminals ofan alternating current source. The thermionic cathode 24 of the lampdevice is connected by lead 29 to the mid-point of the secondary 26.Said transformer 27 has another secondary 30 and the circuit comprisinglead 31, primary 34 of the transformer 34, 35, inductance 33 andvariable resistance 32 is connected to said secondary 30. Saidinductance 33 and said resistance 32 are connected in parallel. Thegrids 7 and the cathodes 5 of'theregulatory devices are connected to theone of the terminals 35 of the transformer 34, -35, resistances 36 beingconnected into the leads to said grids 7.

' The apparatus shown in Fig. 3 is started into operation in thesamemanner as that shown in Fig. 1, that is, the cathodes 5, 5 and 24 arepreheated before the operating potentialis applied to the apparatus. Theregulatory devices control the flow of current through the lamp devicein the same manner as that shown and described in Fig. 1. In this case,however, current flows through the lamp device phase of the alternatingcurrent due to the two anode structure of said lamp device and the lampdevice appears continually luminous, more so than the lamp device ofFig. 1.

The embodiment of my invention illustrated in during a part of each ofFig. 3 and its operating characteristics are the same. It will beunderstood, of course, that the gaseous electric discharge lamp deviceis operable on a polyphase alternating current source whereanappropriate number of anodes is provided in said lamp device.

What I claim as new and desire to secure by Letters Patent of the UnitedStates 1. In combination an electric discharge lamp device-of theelongated luminous positive column type comprising an envelope, agaseous atmosphere therein, and electrodes sealed therein, a currentsupply for said device which periodically falls to zero, and a currentcontrol means connected in series with said device comprising acontainer, a gaseous atmosphere therein, electrodes and a grid sealedtherein, and control means connected to said grid, said grid controlmeans being adjustable to time the duration of current impulses in saidcurrent control means and said lamp device whereby the mean value ofcurrent flow through the lamp device is controlled.

2. The method of controlling the mean current value of current flow ina. gaseous discharge lamp device of the elongated luminous positive 001-

